signs of climate tipping points

I've been posting about far from equilibrium conditions and tipping points in Climate Destabilization in another group, Hang With Friends. As folks concerned about ecology, I thought you'd like a link to that discussion. Climate Destabilization and Weather Variability

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...if temperatures rise too fast there is a “runaway effect” as the microbes are producing heat so fast it cannot be released and builds up, potentially causing fires. Gases also build up eventually causing a huge ‘burp’ or explosive release of carbon into the atmosphere all at once.

“If you put your hand to a compost heap it is warm,” he said. “It is exactly what is happening in peat soils around the world as organic matter breaks down.

The compost bomb also causes a positive ‘feedback loop’ as the hotter the soil gets the harder the microbes work, causing yet more heat. Also the gases released cause more global warming.

...there is evidence of a ‘compost bomb’ around 55 million years ago that caused a huge amount of carbon to be released into the atmosphere all at once.

Scientists are also investigating whether a ‘compost bomb’ caused the peatland fires around Moscow a couple of years ago.

As he says, peatlands cover 3% of the land area. So the imagination boggles if much of it melts and composts quickly. The same process could take hold in dead forests elsewhere, as drought, pests, and floods from climate destabilization take their toll.

As the changes in an ecosystem pile up, they can push the system past a “critical threshold,” and then the change can become extremely fast (in relation to geological timescales) and unstoppable. And in a review in the journal Nature, researchers suggest that the same thing is happening to the whole world: Humans could be driving Earth’s biosphere towards a tipping point beyond which the planet’s ecosystems will collapse abruptly and irreversibly. [emphasis mine]

Their emphasis on unstoppable irreversible collapse is new to me. Most previous articles downplayed that aspect.

Climate patterns that repeat, such as monsoons and El Niño, could shift quickly.

Tim Lenton, a climate scientist at the University of Exeter in England, has identified a handful of climate systems that could reach tipping points in the not-too-distant future. These are not so much related to global average temperatures — the main metric for climate-change arguments — as they are to patterns of climate that repeat themselves each year.

El Niño is one such pattern...Another is the West African monsoon... The most frightening prospect that Mr. Lenton has found is the vulnerability of the Indian monsoon....the monsoons could change suddenly. Mr. Lenton’s analysis shows this could occur in a remarkably short time. The monsoons could be here one year, then gone the next year.

Other possible tipping points are the melting of the North Pole’s sea ice, Greenland’s glaciers and the Antarctic ice sheets, and the destruction of the Amazon rain forest and Canada’s boreal forests.

...sudden shifts in climate patterns may already be happening.

We need a tipping point in climate politics, where all of a sudden we start paying attention. [emphasis mine]

Another feedback to accelerate temperature rise just emerged from ice core data. "...contrary to previous opinion, the rise in temperature and the rise in the atmospheric CO2 follow each other closely in terms of time." Scientists had known that when it gets warmer, CO2 rises, but thought it took up to 1,000 years, which would have given us time. Now we learn that it happens within a hundred or a few hundred years at most.

The green line is temperature. The red and blue lines are separate samples of CO2 in ice core air bubbles.

"Our analyses of ice cores from the ice sheet in Antarctica shows that the concentration of CO2in the atmosphere follows the rise in Antarctic temperatures very closely and is staggered by a few hundred years at most," explains Sune Olander Rasmussen, Associate Professor and centre coordinator at the Centre for Ice and Climate at the Niels Bohr Institute at the University of Copenhagen.

A possible mechanism for the coupling of warming ocean and CO2 rise may be emerging. In the previous article a theory was presented

He explains that one of the theories is that when Antarctica warms up, there will be stronger winds over the Southern Ocean and the winds pump more water up from the deep bottom layers in the ocean where there is a high content of CO2 from all of the small organisms that die and fall down to the sea floor and rot. When strong winds blow over the Southern Ocean, the ocean circulation brings more of the CO2-rich bottom water up to the surface and a portion of this CO2 is released into the atmosphere. This process links temperature and CO2 together and the new results suggest that the linking is closer and happens faster than previously believed.

New data has emerged pinpointing how CO2 sequestration in the Southern Ocean occurs.

The team of British and Australian scientists found that currents that take carbon from the surface to the depths occur at specific locations, not uniformly across the ocean as previously thought.

They found that a combination of winds, currents and whirlpools create conditions for carbon to be drawn down into the deep ocean to be locked away for decades to centuries. Some of the plunging currents were up to 1,000 km (600 miles) wide.

Scientists worry that a warming planet could disrupt this natural pattern by changing wind patterns and ocean currents.

"Climate change will definitely interact with this process and modulate it,"... [emphasis mine]

So stronger winds over the Southern Ocean might disrupt the particular combination of winds, currents and whirlpools that we've relied upon to draw down CO2 -another feedback to accelerate climate destabilization. At least locating the critical areas will allow for monitoring.

Humankind is facing an imminent threat of extinction, according to new research released on Wednesday by the science journal Nature. The report Approaching a state shift in Earth’s biosphere reveals that our planet’s biosphere is steadily approaching a ‘tipping point’, meaning all ecosystems are nearing sudden and irreversible change that will not be conducive to human life.“We have reason to believe the change may be abrupt and surprising,” said co-researcher Arne Mooers, a professor of biodiversity at Simon Fraser University in Canada’s British Columbia.

“The data suggests that there will be a reduction in biodiversity and severe impacts on much of what we depend on to sustain our quality of life, including, for example, fisheries, agriculture, forest products and clean water. This could happen within just a few generations,” stated lead author...

“My colleagues who study climate-induced changes through the Earth’s history are more than pretty worried,” he said in a press release. “In fact, some are terrified,” said co-researcher Arne Mooers,...[emphasis mine]

The light green represents lightly affected ecosystems and the dark green terrestrial ecosystems that have undergone a state shift. Notice how the percent which has undergone state shift accelerates.

James Hansen warns that severe weather is covering 50 to 100 times as much of the globe as it did thirty years ago. While average global temperature rises slowly and steadily, "the extremes are actually becoming much more frequent and more intense worldwide."

Such events used to be exceedingly rare. Extremely hot temperatures covered about 0.1 percent to 0.2 percent of the globe in the base period of our study, from 1951 to 1980. In the last three decades, while the average temperature has slowly risen, the extremes have soared and now cover about 10 percent of the globe.

Such events, our data show, will become even more frequent and more severe. [emphasis mine]

Every bell curve in the animation shows the distribution of anomalies for an 11-year period. The numbers along the bottom represent temperature in terms of standard deviations from the seasonal mean of the 1951-1980 base period, shown below.

You'll see that grey indicates recorded temperatures within one standard deviation of the mean. Red is from a half standard deviation above normal to just over three standard deviations above normal for the very few extremely hot days.

This is the final frame showing 2001-2011.

Notice how the entire bell curve has flattened and shifted far right. Now many temperatures are four and even five standard deviations above the base period mean. What used to be normal (grey) is now at least a standard deviation below the new mean. Much more than half of the last decade's recorded temperatures are (red), hot, very hot and the new extremely hot.

Consider that so far this year's data will be shifted even further right.

Sixty trees sampled at Yale Myers Forest in northeastern Connecticut contained concentrations of methane that were as high as 80,000 times ambient levels. Normal air concentrations are less than 2 parts per million, but the Yale researchers found average levels of 15,000 parts per million inside trees.

"These are flammable concentrations,"...

"Because the conditions thought to be driving this process are common throughout the world's forests, we believe we have found a globally significant new source of this potent greenhouse gas."

In addition to increasing a powerful greenhouse gas, fungi ridden old trees would be gas bombs in an advancing wildfire.